This invention relates to cellular communications and, in particular, to a mobile subscriber station that provides wireless telecommunication services in both the terrestrial (ground-based) and non-terrestrial regions.
Problem
It is a problem in the field of cellular mobile telecommunication services to provide customers with high quality communication services in a unified manner via a wireless communication medium. Existing cellular mobile telecommunication systems serve terrestrial (termed ground-based herein) mobile subscriber stations, but this service was traditionally not extensible to non-terrestrial mobile subscriber stations due to signal interference problems between ground-based and non-terrestrial mobile subscriber stations. The above-noted U.S. Patents disclose a non-terrestrial mobile telecommunication system and a mobile subscriber station operable in such a system, which provides subscribers with cellular mobile telecommunication services in the non-terrestrial region. However, the mobile subscriber stations used in the ground-based cellular mobile telecommunication system and the mobile subscriber stations used in the non-terrestrial cellular mobile telecommunication system are architected to operate in only their associated cellular mobile telecommunication system.
Thus, the existing mobile subscriber stations are incapable of being used both in ground-based cellular mobile telecommunication systems and non-terrestrial cellular mobile telecommunication systems. Therefore, subscribers must presently use one mobile subscriber station for the ground-based cellular mobile telecommunication system and another mobile subscriber station for the non-terrestrial cellular mobile telecommunication system. Each of these mobile subscriber stations has an assigned telephone number and the communication services provided to the subscriber are therefore disjunct. There is presently no mobile subscriber station or cellular mobile telecommunication system that enables the subscriber to receive wireless cellular mobile telecommunication services in a unified manner in both the terrestrial (ground-based) and non-terrestrial regions.
Solution
The above described problems are solved and a technical advance achieved in the field by the ubiquitous mobile subscriber station of the present invention which enables the subscriber to receive wireless cellular mobile telecommunication services in a unified manner in both the terrestrial (ground-based) and non-terrestrial regions. The ubiquitous mobile subscriber station extends the usage of existing cellular mobile telecommunication frequencies allocated for ground-based cellular communications to non-terrestrial cellular communications in a manner that avoids the possibility of signal interference between the ground-based and non-terrestrial mobile subscriber stations. In particular, the ubiquitous mobile subscriber station automatically transitions between the communications paradigm used in ground-based cellular communications and the communications paradigm used in non-terrestrial cellular communications as a function of the present location of the ubiquitous mobile subscriber station. The subscriber therefore can use the ubiquitous mobile subscriber station in all locations for uninterrupted wireless communications services. In addition, the non-terrestrial capabilities of the ubiquitous mobile subscriber station can be used to implement data transmission capabilities for use in the aircraft to provide Flight Information Services, real time monitoring of aircraft operation, as well as enhanced data communication services for the passengers in the aircraft.
The multi-dimensional cellular telecommunication network is seamless and the existing ground-based cell site transmitter/receiver antenna installations can be used to serve non-terrestrial mobile subscriber stations by the addition of non-terrestrial antenna elements. These non-terrestrial antenna elements create an antenna pattern which is insensitive to the reception of ground-originating or ground reflected signals and which antenna pattern is transmissive only in a skyward direction. In addition, the polarization of the signals produced by the non-terrestrial antenna elements is a polarization that is different than and preferably substantially orthogonal to the polarization of the ground-based cellular radio signals, such as a horizontal polarization, to thereby minimize the possibility of interference with the vertically polarized ground-based cellular radio signals. Furthermore, the control signals exchanged between the non-terrestrial mobile subscriber stations and the non-terrestrial cell site controller are architected to avoid the possibility of interference with ground-based cell site transmitter-receiver pairs. In particular, the control channels used for the non-terrestrial mobile subscriber stations are selected such that the control signals transmitted in these channels are unrecognizable to the ground-based mobile subscriber stations and ground-based cell site transmitter-receiver pairs so that even if broadcasts from a non-terrestrial mobile subscriber station reach a ground-based mobile subscriber station or cell site transmitter-receiver pair they cannot be interpreted and are rejected out of hand. Optionally, the non-terrestrial system can switch uplink and downlink frequencies to be the opposite of ground-based mobile subscriber station pattern. In this manner, non-terrestrial cells can be created in the region of space adjacent to and overlying the existing ground-based cells and the existing cellular communication frequencies allocated for ground-based cellular telecommunications can be reused for non-terrestrial cellular telecommunications without the possibility of interaction between the existing ground-based cellular mobile telecommunication system and the non-terrestrial mobile subscriber stations. To the mobile telecommunication switching office, the non-terrestrial cells all operate in harmony with the existing ground-based cell sites with no discernible differentiation among cells or stations, be they ground-based or non-terrestrial in nature. In this manner, the existing two dimension mobile cellular telecommunication network is extensible to create a multi-dimensional cellular mobile telecommunication system which makes use of the presently allocated cellular radio frequencies and presently provided services. In this environment, the ubiquitous mobile subscriber station automatically transitions between the communications paradigm used in ground-based cellular communications and the communications paradigm used in non-terrestrial cellular communications as a function of the present location of the ubiquitous mobile subscriber station. In addition, the non-terrestrial capabilities of the ubiquitous mobile subscriber station can be used to implement data transmission capabilities for use both in the aircraft to provide Flight Information Services, real time monitoring of aircraft operation, as well as to provide enhanced data communication services for the passengers in the aircraft. This data communications capability can be used to link the aircraft to a private data communication network as well as providing access to public data communication networks. Thus, the subscriber who is equipped with a ubiquitous mobile subscriber station can maintain a single set of identification data (MIN, ESN) regardless of their location in the multi-dimensional cellular mobile telecommunication system and independent of the mode of operation: ground-based cellular communications or non-terrestrial cellular communications